“I’ve not worked on a site like that in a long, long time,” a source told Construction News.

Mace, the contractor firm, denies the allegations (Getty)

“There were people off their heads, drinking cans first thing in the morning before going on to site and snorting coke in the toilets.”

Contractor firm Mace, that runs the stadium site, has moved to deny the claims.

“Mace strongly refutes the image of our project painted by these anonymous allegations,” said a company spokesman.

“The health, safety and well-being of everybody is, and has always been, a core value at Mace and any suggestion that our rigorous standards around best practice or drugs and alcohol had been broken would be taken extremely seriously.

“We carry out regular random drugs and alcohol testing to ensure that our rules are enforced throughout our supply chain. Any concerns about specific health and safety risks should have been flagged to Mace health and safety staff on the project.”

Tottenham’s new ground was meant to open on 15 September, but health and safety issues have held that up.

Spurs have continued to play home games at Wembley where possible, and will host Watford in the third round of the Carabao Cup at Milton Keynes’ Stadium MK.

Unnamed sources have also told Construction News that mistakes have contributed to the delays at the stadium, with electrical wiring forced to be ripped out because air-conditioning units had not been installed properly.

How the new Tottenham stadium will look hosting NFL fixtures (Getty )

“The new Tottenham Hotspur Stadium is one of the UK’s most complex and innovative projects,” continued Mace’s statement.

“The club and the construction team are working diligently to complete the iconic stadium as soon as possible.

“Although these delays are obviously frustrating, once complete the new stadium is going to leave a fantastic, lasting legacy and will be a project everyone involved will be proud to be associated with.

“As you would expect, the number of operatives on site has reduced as sections of the stadium have begun to complete, in line with our programme.”